An investigation of CO2 extraction of marigold (Calendula officinalis L.)

Abstract

Essential oil content (0.05 %) of marigold (Calendula officinalis L.) was determined using the official steam distillation procedure. High-pressure CO2 extraction of plant material under supercritial (100, 200 and 300 bar and 40 degrees C) and subcritical (60, 90 and 120 bar and 15 degrees C) conditions for 3 h was investigated. It was found that the increase in the pressure promoted an increase in the yield. The essential oil contents obtained from the investigated CO2 extracts by steam distillation were significantly higher (1.52-2.70 times) and increased with pressure. Major constituents of the oil, identified using GC-MS and GC-FID, were alpha-cadinol (26.54 %), T-cadinol and T-muurolol (9.80 %), gamma-cadinene (2.99 %), hexadecanoic acid (2.95 %), and ledane (2.45 %). In addition, the essential oils of the CO2 extracts contained delta-cadinene (6.50-19.87 % under supercritical and 16.09-19.41 % under subcritical conditions), which was not found in the essential oil obtained from the plant by steam distillation. The extraction kinetics was investigated at 200 bar and 40 degrees C. The total extract obtained after 10 h of extraction was 6.54 % and essential oil content in it, refering to plant material, was 0.209 %, which is 4.16 time more than the one determined by the standard steam distillation procedure.

Određen je sadržaj etarskog ulja nevena (Calendla officinalis L.) primenom postupka destilacije vodenom parom (0.05 %). Ispitivana je ekstrakcija ugljen-dioksidom pod visokim pritiskom u superkritičnoj (100, 200 i 300 bar i 40°C, i tečnoj (60, 90 i 120 bar i 15°C) oblasti ekstrakcije. Nađeno je da se prinos ekstrakcije povećava sa povećanjem primenjenog pritiska. Sadržaj etarskog ulja u ispitivanim CO2 ekstraktima bio je veći (1,52-2,70 puta) od onog dobijenog primenom postupka destilacije vodenom parom i povećavao se sa porastom pritiska. Glavne komponente etarskog ulja, određene primenom GC-MS i GC-FID, bile su α-cadinol (26,54 %), T-cadinol i T-muurolol (9,80% γ-cadinene (2,99 %), heksadekanoična kiselina (2,95 %) i ledane (2,45 %). Pored navedenih komponenata, etarska ulja iz CO2 ekstrakata sadržala su i δ-cadinene (6,50-19,87 % u superkritičnoj i 16,09-19,41% u tečnoj oblasti ekstrakcije) koji nije nađen u etarskom ulju dobijenom primenom postupka destilacije vodenom parom. Kinetika ekstrakcije ispitivana je na 200 bar i 40°C. Ukupni ekstrakt dobijen nakon 10 sati ekstrakcije bio je 6,54% računato na biljni materijal, dok je sadržaj etarskog ulja u njemu bio 0,209%, što je 4,16 puta više od sadržaja ulja određenog destilacijom biljnog materijala. .